When I render the following 2htdp/image expression:
(overlay (text "3" 120 "yellow") (square 120 "solid" "dark brown"))
I get a picture that looks like this:
Note that it's not centered. If an actual Helvetica font is used, it produces a centered 3. Also if I use some other font like 'default, it works correctly:
To understand why, consider this program:
(require racket/draw)
(define text-sizing-bm (make-object bitmap-dc% (make-object bitmap% 1 1)))
(define ft (send the-font-list find-or-create-font 120 'swiss 'normal 'normal #f 'default #t))
(send text-sizing-bm get-text-extent "3" ft)
This produces (values 67.0 121.0 33.0 0.0) on my machine but (values 67.0 139.0 27.0 0.0) on a different machine (thanks @ccshan) with Helvetica installed.
It's not clear to me what the bug is here but the drawing definitely seems wrong.
When I render the following
2htdp/imageexpression:I get a picture that looks like this:
Note that it's not centered. If an actual Helvetica font is used, it produces a centered 3. Also if I use some other font like
'default, it works correctly:To understand why, consider this program:
This produces
(values 67.0 121.0 33.0 0.0)on my machine but(values 67.0 139.0 27.0 0.0)on a different machine (thanks @ccshan) with Helvetica installed.It's not clear to me what the bug is here but the drawing definitely seems wrong.